Cannot suspend laptop in Ubuntu 14.04.3

[reedstrm]

I had a similar issue, failure to suspend. This happened after I had a problem with DisplayLinkManager occasionally going crazy and eating half my CPUs, even if no display was installed. That's another problem, though, which I am owrking around by setting the service to manual launch. When I did that, I can no longer suspend, because of how the pm suspend script is written. I added this stanza at the top:

if [ ! -e /usr/lib/displaylink/PmMessagesPort_out ]; then
exit 0
fi

So the script does not fail if the manager service isn't running.

Ross

P.S. the informative log for this case is /var/log/pm-suspend.log
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